1. Technical Field
The present invention relates to a substrate processing apparatus and an attaching/detaching method of a reaction vessel, and for example relates to the substrate processing apparatus used in a semiconductor manufacturing apparatus and an attaching/detaching method of the reaction vessel.
2. Background Art
FIG. 20 shows a sectional view of a batch type vertical processing furnace that simultaneously processes a plurality of wafers used in a conventional substrate processing apparatus.
A vertical processing furnace 302 is provided in a casing not shown. This vertical processing furnace 302 is composed of a heater unit 306 and a reaction vessel 307 inserted into the heater unit 306. The reaction vessel 307 is composed of a reaction tube 303 and a furnace throat flange 309 for supporting the reaction tube 303. The reaction tube 303 is composed of an outer tube 305 and an inner tube 304 provided in the outer tube 305. The furnace throat flange 309 is made of metal (for example, see patent document 1). A boat 317, with a plurality of wafers 200 loaded in a multistage manner, is inserted into the inner tube 304. The furnace throat flange 309 is closed by a seal cap 319 for supporting the boat 317.
The plurality of wafers 200 loaded in the boat 317 are processed in a process of exhausting residual gas, etc, after reaction from an exhaust tube 331, while supplying gas into the reaction tube 303 from the gas supply tube.
In order to assemble such a vertical processing furnace 302, insert/extraction of the reaction tube 303 to the vertical processing furnace 302 must be performed by using a lower space of the vertical processing furnace 302. The insert/extraction of the reaction vessel 307 to the vertical processing furnace 302 is performed by a boat elevator not shown and an attachment/detachment device (for example, see patent document 2). The reaction vessel 307 is attached from an opening part opened to a lower part of the heater unit 306 fixed to a heater base 351. The reaction vessel 307 needs to be inserted into the heater unit 306 up to an upper side from the exhaust tube 331, because the exhaust tube 331 is protruded, in a state that a part of the reaction vessel 307 is protruded from the heater unit 306. In consideration of a gas flow, the exhaust tube 331 is preferably formed in a cylindrical shape having a large diameter.
However, when the diameter of the exhaust tube 331 is large, a part protruding from the heater unit 306 also becomes longer, thus making the vertical processing furnace 302 larger. Note that by decreasing a height of the reaction vessel 307, processing number of wafers also decreases, which is not preferable because production capability is also decreased. Here, a device to process a large number of wafers by increasing the height of the reaction vessel 307 is called a large batch processing apparatus, and a device to process a small number of wafers by decreasing the height of the reaction vessel 307 is called a small batch processing apparatus.    [Patent document 1]
Japanese Patent Application Laid Open No. 08-120453    [Patent document 2]
Japanese Patent Application Laid Open No. 11-67679
When a reaction vessel structure is applied as it is, the height of the device is increased, thus increasing the height of a clean room, even if the large batch processing apparatus is actually installed in the clean room. Therefore, it becomes difficult to install the reaction vessel 307 in the heater unit 306.
In order to assemble the vertical processing furnace 302, as shown in FIG. 21, the attachment/detachment of the reaction vessel 307 must be performed to the vertical processing furnace 302, by using a transfer chamber 324 as a preliminary chamber adjacently provided in a lower part of the vertical processing furnace 302. The attachment/detachment of the reaction vessel 307 to the vertical processing chamber 302 is performed by using a truck, a boat elevator, and an attachment/detachment jig 300 placed on a seal cap 219.
As shown in the figure, when the exhaust tube 331 is formed in the furnace throat flange 309, unless the wafer processing capability is decreased, the height of the reaction vessel body with the outer tube 305 connected to this furnace throat flange 309 is increased. Therefore, from the restriction of the transfer chamber 324, the outer tube 305 and the furnace throat flange 309 must be separately attached/detached.
In addition, as shown in FIG. 22, under a condition of not changing a device height even when the exhaust tube 331 is integrally formed with the outer tube 305, the outer tube 305 (a part of a designation mark D) does not come out from the heater unit 306 when the outer tube 305 and the furnace throat flange 309 are integrally detached by using the attachment/detachment jig 300, and the outer tube 306 and the furnace throat flange 309 can not be simultaneously attached/detached. Therefore, the outer tube 305 and the furnace throat flange 309 are divided in maintenance, and the attachment/detachment of the outer tube 306 and the attachment/detachment of the furnace throat flange must be dividedly performed in twice or more. Accordingly, a structure of the attachment/detachment jig 300 is complicated, thus generating a time-consuming maintenance work.